Fourteen Days or The Transformation of John Watson
by Lymphadei
Summary: In which John gets a second chance, though not in the way one would ever expect. [Slash]


Hello all! so this was supposed to be a little one-shot, but the little one-shot took steroids, so days of writing and hours of editing later, I present to you my sad, little fluffy fic. Based on a request a dear someone requested on tumblr. I'm sorry it wasn't all baby John, but this all sort of just came out! xD

* * *

 **Day 1**

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, **_14_**

_/\\_/\\_/\\_/\\_/\\_

"John, come _on!_ "

Left at the end of the corridor, follow the white tail coat. Past the long, unlit hall with the broken 'Exit' sign. No possible escape down that path, which meant they would have their perp!

John's feet were slapping against the lino behind him, a steady, stalwart presence at his back; the thrum of their constant connection pulsing just as sure as the exhilarating thump in Sherlock's chest.

Sherlock threw himself up against the wall, the last corner that would lead to a dead-end. John followed suit as Sherlock's mind conjured up every possible outcome of their inevitable confrontation with the erstwhile scientist they'd been on the trail of for nearly a week.

Live human subjects for unauthorized experiments and murder were the least of Dr Förstner's offenses. Not to mention the science community had long since shunned Förstner's earlier work, speculative and incomplete as it was, it'd been determined that the doctor was not of sound mind.

For one of a weaker constitution, the crime scenes were unpleasant and macabre. Förstner was obsessed with the idea that human genetics could be altered, and he was determined to bring absolute findings to the scientific community with the proper evidence to support his claim. Most human subjects hadn't lasted past approximately the first forty-eight hours under Förstner's heavy-handed experiments. High doses of Succinylcholine were found in the victims and ventilators in the abandoned facilities, suggesting that after the drug was administered, he kept the patients alive while experimenting.

Misplaced body parts, half-rotted skin and in some cases, signs of prolonged exposure to radiation, which also caused genetic mutation.

Förstner had been clever, aiding the Yard in their investigation to avoid scrutiny, but he hadn't been expecting Sherlock Holmes. That was his downfall.

Förstner was a trapped animal, and there were only a few possible ways their confrontation could go. One, Förstner would go for a distraction in order to escape, but _what_ exactly he had planned was inconclusive. Two, he would see there was no getting past John and his trigger finger, and wisely allow himself to be restrained until the Yard came to collect him. Three, Förstner would die attempting something foolish.

Two was highly unlikely. Förstner was a proud man and considered himself slighted by the scientific community, wanted to prove himself and thought he could be close to a breakthrough. He wouldn't give up easily. Sherlock _loved_ a challenge.

Sherlock turned to John who was just as calm and solid beside him as always, Sig Sauer clutched in his fist at the ready, safety switched off. Deep blue eyes watched him back, waiting for his command. Sherlock wanted to kiss him, but the Work came first (always came first) and the light in John's eyes indicated that he would be very amenable for whatever Sherlock had planned for later.

Sherlock nodded and John mirrored the motion, turning his mind to the crucial moment ahead. Sherlock turned to peak around the corner, noticing a door on the right, ajar. The short hallway was empty.

"Doctor," Sherlock called, "the game is up! There are only three ways in which this situation can end, one of which would be unfortunate for you. I advise you to think about your next course of action very carefully!"

The warning was met with a strict silence, just the constant buzz of the flickering fluorescent lights above them. Sherlock set out across the hall, staying against the wall as they edged towards the door.

"Sherlock..." John's expression was guarded, a caution in the soft uttering of Sherlock's name. "I've a feeling something isn't right about this."

Sherlock paused, flashing an irritated, impatient glare at his partner. "Last time you had a feeling, you turned out to be wrong. Let's at least attempt to use our brains this time, John. _Think_ , there's no way out but through that door. I've studied the blueprints of this building through and through, so unless Förstner can conjure up a magical door," Sherlock rambled on in a harsh whisper, gesturing widely with his hands, "then the only way he's getting out of this building is by killing us, and I assure you, John, that will not be happening."

John frowned, blue eyes burning as he met Sherlock's glare without hesitation. "For all we know, he could have some kind of weapon in there!"

"Of course he does, John," Sherlock snapped loftily, "he's a criminal."

"Oh, so your shoddy logic tells you we should go gallivanting in there with a madman, _without_ waiting for backup!"

"Lestrade is on his way-"

"Yes, but he's not here _now_ ," John growled, and Sherlock noted that he was resisting the urge to grab his hair and pull, which was synonymous to the involuntary eye spasm John developed when frustrated.

Sherlock rolled his eyes and growled below his breath. "Every second we spend arguing over this, our perp is closer to possible escape. Now if you don't _mind_ , we will go in, incapacitate him and wait for those idiots at the Yard to play catch up!"

John's jaw was clenching rhythmically - unhappy but agrees that they shouldn't delay any longer - but he nodded, conceding to Sherlock's logical explanation. John knew Sherlock was right. He was _always_ right.

Taking one last calming breath, Sherlock edged closer to the door, until he was standing just out of view of the opening. One last look at his partner and John came round and swung in first, gun held out in front of him and Sherlock just behind him.

Sherlock's eyes darted around the room taking in everything. It _was_ an old hospital building, abandoned around the late eighties. The room was a mess, stockpiled with outdated medical equipment and a water stained curtain that hung limply around an old cot. There was so much clutter, in fact, that it would be easy to create the element of surprise.

That, Sherlock had not counted on.

There was a loud rustle and then John was locked in a choke-hold by a deceptively frail figure in a lab coat. Wiry grey hair stood out in every which way, and Förstner's green eyes bulged from their sockets, darting about wildly. It was the needle in his hand that made Sherlock freeze, the point pressed against John's jugular vein.

"You should've left well enough alone, Holmes. This isn't your problem to deal with, but it will be if you don't turn back the way you came." For all that Förstner appeared manic, his voice was sombre and steady, almost regretful. "Drop the gun, you," he demanded, jerking his arm tighter around John's neck.

"Safety is off," John choked out, but the arm around his throat tightened in warning.

"I don't care. Drop it."

John did as bade, tossing his gun off the side, tracking it across the room where it slid to the corner.

"Now," Förstner began, "unless you want your partner, here, to die, I suggest you back up through that door. Hands up."

Sherlock put his hands up, unable to tear his eyes away from John. This was a situation they could handle. Not the first time John had been used for leverage against Sherlock, yet even after the debacle with Moriarty and Magnussen, Sherlock found that the effects of seeing John in the hostage position hadn't lessened over the years.

Sherlock needed to get Förstner talking until the cavalry arrived.

"Your should know that you're not going to get out of the alive. I don't forgive threats easily."

It wasn't the smartest thing to say to a man holding the life of his partner in hand, to which John rolled his eyes exasperatedly, but the threat would get him talking.

"You're not as much of a genius as they say you are if you can threaten a man who currently has the upper hand," Förstner growled, his composure finally giving way to reveal the insanity beneath. "It's just your luck that I'm feeling generous today."

Sherlock never tore his gaze away, but in his mind, he pulled up a picture of the room and all of its clutter, looking for anything that could be used as a weapon. John's life was at stake, so any course of action had to be quick, might be dirty, but even if it only provided a distraction, it would work.

All the old equipment was heavy and large, as electronics tended to be in the eighties. Besides the plastic chairs shoved one atop the other in the corners, there wasn't much that could be used in the way of a weapon. The gun was too far in the corner off to his left. All it would take was a millisecond for Förstner to realize Sherlock's plan and depress the drug into John's vein. Sherlock was quick, but not quick enough. He needed a proper distraction.

"Even if you planned on presenting your evidence to the scientific community, they would have shunned you anyway. Your wife left you after she walked in on you experimenting on the family dog, thought that you'd abandoned your faculties. She informed your colleagues of what you were doing and they ousted you. Now you're angry and you want to show them that you were right all along." Once his deductions began, there was no stopping them from tumbling past his lips. The more he spoke, the more furious Förstner became, which in turned, turned his attention from John to Sherlock.

"Shut your mouth," Förstner spat, spittle flying from his lips. "You think you're so _clever_."

Sherlock blink, tilted his head and spread his raised fingers. "I _am_ clever, doctor."

In the end, he wasn't clever enough to realize that Förstner hadn't taken the bait.

"Yes, well, I hope you were clever enough to see this coming!" Förstner slammed his thumb down on the syringe and depressed it until all of the clear liquid released into John's veins.

The minute Förstner stopped speaking, Sherlock realized it was too late to stop him and lunged for the gun. Hopefully the medical team would arrive quickly enough to combat whatever Förstner injected into John's bloodstream.

John dropped to the ground like a stone, his body writhing and seizing against the dusty lino. Sherlock grabbed the gun and turned it on Förstner's quickly retreating back, and pulled the trigger until a spray of blood and brain matter were trickling down the back of his blown out cerebellum.

Förstner fell and didn't get up.

Sherlock tossed the gun away and knelt down besides John's body, feeling for his pulse as John's mouth began to froth, eyes open and unseeing.

He'd gravely miscalculated.

History pointed toward the perp turning on Sherlock in a rage as they were often wont to do, which would in turn allow John the chance to break the hold and incapacitate the perp. How could he have been so careless? This was John's life; _John_.

 _Stupid! Stupid_ , he wanted to scream.

Sherlock whipped his phone out of his pocket and dialed Lestrade's number, swearing when he didn't pick up on the first ring.

"Sherlock, we're here. Where are you?"

"Third floor, down two halls, take a left to the dead end corridor. John needs medical attention, now, Lestrade," Sherlock rattled off, dropping the phone as Lestrade raised his voice on the other end.

"Medical attention? Christ, what happened- Sherlock? Sherlock!"

"John!"

Sherlock was shaking him, but John was still, his body limp and compliant under Sherlock's touch. "John!" Sherlock leaned down, placing his ear close to John's mouth.

No breath.

Sherlock didn't waste any time, pinching John's nose as he placed his lips against John's, desperate to breathe life into him.

Breathe twice.

He pulled away and placed his hands against John's chest, one over the other, and compressed. Thirty times in succession, only to repeat the process when John showed no signs of recovery.

Sherlock couldn't breathe, couldn't think past the fuzz in his brain, John's name whirling round in his head on repeat. He'd miscalculated. It couldn't be right. Sherlock would not let it be the end of his time with John, not after everything they'd been through together.

The divorce with Mary had been finalized and there was no more Moriarty (finally) nor the dark cloud of Magnussen hanging over their heads. Now, there was John, not breathing and the terror clawing its way up Sherlock's chest, because who was he without John Watson.

Freak.

 _I don't have friends..._

Psychopath.

 _... I've just got one..._

Alone.

Sherlock's hands were hurting where they compressed John's chest, growing tired and drained of the strength it would take to keep going. He could hear boots beating against the lino in the hall, the buzz of wheels against the floor as they pushed the stretcher into the room. All of it was background noise. None of it mattered. He kept going.

Someone was shouting John's name over and over, and Sherlock nearly snarled for them to shut up, until he realized it was himself forming those words, begging for John to breathe.

Eventually, hands began to pull him away, and Sherlock let them, because the medics had the equipment he didn't, and even if it felt like his chest was tearing itself apart, Sherlock let them take John away on the stretcher.

Lestrade came to Sherlock and gripped his shoulders, growling at Sherlock to tell him what happened.

Unwittingly, he remembers John's account of his confrontation with Donovan.

 _Sherlock Holmes will be the one that put it there..._

Sherlock couldn't open his mouth to speak. Whether by his own hand or Förstner's, he was the one that put John's body there. Sherlock's imbecilic miscalculations. Why didn't he _see_?

Förstner was a rabid animal backed into a corner. Of _course_ he would respond with violence!

" Damn it, Sherlock, I need to know what happened!"

Lestrade was shaking him and Sherlock was trembling, his knees were unsteady.

 _John._

 _Sherlock Holmes will be the one that put it there._

 _John..._

 _Sherlock Holmes will be the one that put it there._

 _John!_

Slowly, Sherlock turned red-rimmed, glassy eyes on Lestrade, distant and blurry. "Förstner injected John in the jugular vein. I don't know what was in the syringe. We have to test it as soon as possible."

It was automatic, without inflection. The words simply came and Sherlock was just the conduit. It was an out of body experience. He was wherever John was at the moment, floating between life and a dark abyss.

Lestrade swore and swept out the room behind the medics, leaving Sherlock alone with forensics, taking pictures of Förstner's cooling body. Unfortunately, John's gun had been bagged as evidence.

Sherlock followed listlessly, his mind relentlessly tracking over all the possible outcomes of their confrontation with Förstner.

 _I've a feeling something isn't right about this..._

John always said that. He'd never been so observant before.

Sherlock's phone was ringing, a subtle vibration through the wool of his coat.

 ** _Mycroft_**

The only one that always called instead of leaving a text, as Sherlock preferred. Always the infuriating busybody.

It was a chilly night, but Sherlock couldn't feel it as he stepped outside the hospital, could only tell by the billow of steam when he exhaled.

He walked through the crime scene, ignoring the piteous states and baleful glares - _Oh, so your shoddy logic tells you we should go gallivanting in there with a madman,_ without _waiting for backup_ \- until he was at the yellow tape.

The ambulance was gone, presumably to the closest hospital (not enough brain capacity to sort which; John filled every empty space) but Lestrade was waiting for him at his car.

"Get in," Lestrade ordered, and for once, Sherlock took the passenger seat without a word.

Sherlock felt empty, hollow. Kept waiting for his phone to receive a text from John, soothing his worries, laughing it off. His phone stayed dreadfully silent.

"...should have waited, Sherlock." Sherlock came to at the tail end of Lestrade's reprimand, not regretful to have missed it.

Unsurprisingly, it was Barts they pulled up to shortly thereafter. Even then, Sherlock felt that inexplicable pull in his abdomen, that acute pain whenever he thought of his final moment with John before his three year sojourn across the world to take down Moriarty's vast network.

As they parked, Sherlock's phone began to vibrate again, and when he failed to pick up, Lestrade's followed suit.

The quick glance in Sherlock's direction alerted him to the fact that Mycroft was on the other end of the line, and Sherlock didn't _want_ to know why he was calling. Even if he already knew.

Lestrade's face was grave when he hung up and stared straight ahead, his soft brown eyes as empty as Sherlock was.

Sherlock laid his head against the window and forced himself to stay together. He could implode later, when he was alone. He closed his eyes.

Dark blue eyes, alight with excitement and a love that Sherlock would never deserve, no matter how many sacrifices he made for John.

The world was still turning, but it all fell away for Sherlock, because John _was_ his world, and without his world, there was no place for Sherlock to go.

He'd planned to take John home that night, feed him (Chinese was their preferred spread after a successful case), and then take him to their bedroom where they would stay until the next afternoon.

Sherlock didn't realize he was trembling until Lestrade placed a hand over his shoulder, and then his head was in his hands. His body attempting to curl in on itself as he swallowed and swallowed back the swell of emotions.

 _Deep blue eyes._

That infinite trust that John granted him with, that moment right by before they swept in the room, and every second preceding that. John had _trusted_ him.

 _Disheveled blond hair._

Sherlock was rocking back and forth, somewhere out at sea on a boat weathering a storm. A pitch black nothingness lit by strokes of lightning stretching like spindly fingers across the sky.

 _Soft, gentle lips and a large nose that tipped up at the end. Sherlock loved to kiss it, only to annoy John._

Only he wasn't at sea, and his body was rocking back and forth until Sherlock began to grow sick.

 _His John._

Never coming back.

Lestrade drove him home because Sherlock didn't want to see John, didn't want his last memory of his partner as just another cold corpse in the morgue. That wasn't his John. The body would be buried and become food for other organisms and cease to be John Watson.

Mrs Hudson was waiting on the steps, ready to smother Sherlock and drown him in soup that was too salty and pastries too sweet. She was crying, but Sherlock didn't want to comfort her.

What for?

John was gone. It wasn't as if he would ever be there to rebuke Sherlock for being rude. It wasn't as if he could come back. He stopped by Mrs Hudson and accepted her hug with numb arms and a blank face.

Upstairs, Mrs Hudson wrapped a quilt around his supine body on the couch, and Sherlock closed his eyes and allowed himself to implode (finally).

In his mind palace, everything began to crumble. The doors in every hall we're cracked and splintered and the stairs trembled beneath his feet as he traversed them one step at a time. If everything collapsed, it would be fine, because without John, none of it was meaningful.

The windows were shattered, painted glass, indigo, cut Sherlock's feet as he walked. The stairs fell away behind him until there was nothing left but a gaping hole.

Mycroft, Molly, Lestrade, even Irene, they were all there watching him. Mycroft was shaking his head sternly ( _caring is not an advantage_ ) and Molly was watching him with soft, soulful brown eyes ( _you look sad when you think he can't see you_ ). Greg with his disapproval and fondness, his anger ( _you should've waited, Sherlock_ ) and Irene's flirtatious condescension ( _do you know the big problem with a disguise, Mr Holmes? However hard you try, it's always a self-portrait_ ).

Well there was nothing to hide anymore. There was no happiness, no hatred towards Förstner or victory in his death, there was simply nothing.

He defended happily into that darkness.

* * *

...

 **Day 2**

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, _**13**_

There was a vibration against his stomach, an intermittent hum against his shirt, the same one from the night before.

It was damp and sticky with sweat, Mrs Hudson's quilt a heavy weight over him. His mind was blessedly silent, no deductions, no tearing itself apart without a case, nothing except for the emptiness John's absence left behind.

The phone buzzed quietly, and Sherlock lifted it up to his eyes.

 **Molly Hooper**

Probably to give her condolences. Twelve messages since sometime around early morning. It was noon.

The most recent:

 **Text message: Molly Hooper**

 **Come to the morgue. I can't explain right now, but please. You need to see this.**

Molly and her tendency to hyperbolize issues, just as she had done during the Magnussen case, after John forced Sherlock to take a urine test. Sherlock didn't know whether to ignore it or call her back. He didn't feel like talking to anyone, felt even less like hearing her stumble over sympathies.

Before he could throw the phone away, it began to vibrate in his hand. Molly, again.

"What is it," Sherlock growled. He didn't want her to tell him to go see John. That wasn't John, and would never be again.

On the other end, Molly inhaled tremulously, and in the background, a soft coo sounded through the receiver. "Sherlock, you need to come down to the morgue. It's John... I don't know how this can be happening."

Another sound, this time louder, like a giggling infant.

Sherlock sat up, his stomach dropping and lifting in a twist of dread and hope that made his head spin. "What happened, Molly? Is John... is he...?"

Molly sniffled. She was crying. "He was last night. I was there, I did his autopsy, but then I came back this morning... Sherlock, you wouldn't believe me." A pause. "John's not dead, but he's not exactly..."

But all Sherlock could hear was John's not dead, _John's not dead_ , _**John's not dead**_ and all the suffocating hope that came with the statement.

Sherlock hung up without a word, hyperventilating, afraid that he was dreaming. If John was pronounced dead, there was no logical way he could possibly be alive. He hadn't cared to find out what was in Förstner's syringe. The damage had already been done, what sense would it make to know? He'd killed Förstner; a dead man couldn't be prosecuted.

Sherlock's stomach roiled, turned over as he shot up and grabbed his coat, never mind that he was still wearing the same clothes from the night before. John was not there to fuss over him, not there to impress. His clothes were wrinkled, but it would have to do. He needed to see if John were alive, needed to know.

Sherlock stomped down the stairs, ignoring Mrs Hudson as the door to 221A flew open at the noise. He was out the door before she could call him back, and holding his hand out for a cab.

On the ride over, Sherlock felt manic, unable to sit still, prone to glancing at the empty seat beside him where John's warm body would usually be, his thigh pressed against Sherlock's. He didn't miss the furtive looks from the cabbie through the rearview mirror, worried he'd picked up a junkie. Recovering drug addict, perhaps, found a job as a cabbie a last ditch effort to save his family. Unfortunately, the wife was already having an affair.

Sherlock threw him fifty quid and told him to keep the change as he darted out of the cab and into the building, not stopping until he was outside of the door to the lab.

There was a baby, crying. Loudly.

Sherlock pushed the door open and stopped.

Molly turned, carrying a infant boy with a shock of blond hair and wailing loud enough to alert the entire hospital. He stayed near the door, his eyes moving around the room, looking for John.

"Thank God you're here. I didn't know if you were going to show," Molly said, relief causing her shoulders to sag as she walked towards Sherlock. The wails died down to a sniffle as the watery-eyed child observed him curiously.

Sherlock ignored the child and walked past Molly, swinging around the corner with still no sign of John. He turned to glare at Molly, wondering if she'd played him, anything to get him to the morgue, to see John before he was... buried where Sherlock could no longer reach him.

"Where is he," Sherlock growled, looming over Molly.

Molly couldn't meet his eyes, couldn't tear her eyes away from the child. Sherlock thought that he should ask whose child she was holding, where did it come from, but he didn't care. He just wanted John.

"Sherlock, I- I did John's autopsy and locked him up myself... but then I came in, you know, to write up the report and when I pulled out the drawer, well-... I-"

Sherlock watched her closely, growing impatient as he waited for Molly to finish her stumbling explanation so that he could flay her with his words for lying to him. "What," he snapped, "quit stalling and spit it out, woman!"

"I found the baby in the drawer, and John's body was gone!"

The silence that followed was long and ominous, Molly's words a dark cloud that threatened rain and lightning and thunder. Sherlock wanted to scream at her, accuse her of negligence, but he knew that this was beyond that. Then, he looked, _really_ looked at the child.

Blond hair, lighter than John's, but Sherlock remembered a picture of teenage John, with white-blond hair that gradually began to darken over time. Though it wasn't the hair that convinced him.

Sherlock stepped closer, his hands trembling beneath wool of his coat, his eyes growing wide as he came to stand before the infant who stared back in awed curiosity. Cobalt eyes, the color of a turbulent sea in the midst of a storm and there was no mistaking the Watson nose, the upturn at the tip.

Sherlock's chest squeezed as those wide blue eyes tore away, peering around the room and then back to Molly, his little nose scrunching up as he sneezed.

"Molly... this- this isn't possible."

Molly nodded quickly, running her free hand nervously through the strands of hair that fell loose around her face. "I know, which is why I took a bit of DNA and ran some tests. A bit of blood and a strand of hair, saliva. I've done everything."

Sherlock couldn't stop staring, though the infant was no longer paying him any mind, suckling on his tiny fists. Sherlock didn't want to hold him, didn't want to take that chance until he was sure. Sherlock didn't even understand why he was entertaining the ridiculous notion that somehow whatever Förstner injected into John would turn him into an infant overnight. People didn't get second chances like that; science didn't work that way.  
It was impossible, highly unrealistic.

"The results," he enquired.

Sherlock's silence pulled his stare away from the infant and back to Molly, who seemed to be as riveted with the child as he was. She bit her lip and turned her head to look at him.

"It's him."

Sherlock backed up until his flank hit the wall, disoriented and the white spots dancing across his vision didn't help, the fact that he hadn't eaten anything the night before and two days before then while the Förstner case had been ongoing only made things worse. John always did tell him how unhealthy of a habit that was.

Molly was crying again, silently, tears tracking zigzags down her cheeks as she smiled at the tiny infant wrapped in a sheet, in her arms. "The drugs Förstner injected in him didn't kill him. They somehow reset his biological clock, but it could be temporary." Molly wiped her eyes with the back of her free hand before being it back up to cradle the infant's back. "We don't know the long term effects of the drugs, but you should know... Mycroft has already gotten involved."

Sherlock's eyes shot up at that, his spine straightening. Mycroft was going to take John away from him. "He knows."

Molly nodded, bouncing the infant- John, as he became restless. "He came to pay his respects this morning, or so he said. He was here when I opened the drawer."

Sherlock pushed off the wall and walked to where Molly held John protectively against her chest, reaching one hand out tentatively to smooth down the errant strands of John's thin hair.

"Would you like to hold him," asked Molly, shifting the infant in her arms to make it easier to transfer him to Sherlock.

Sherlock was frightened, unsure, reluctant. He'd always been impassive towards children, never wanted any for himself, but then again, this was _John_. Not exactly what he expected or wanted, but this was his partner.

 _When you have eliminated the impossible, whatever remains, however improbable, must be the truth_. How many times had Sherlock told John the very same thing?

He owed it to John to embrace him in any form, take care of John just as he had taken care of Sherlock throughout their partnership.

Sherlock nodded, entranced by eyes too wise to be anything but John's, looking up at him with so much trust.

John was a small, fragile thing in Sherlock's arms, all soft, chubby skin and pink cheeks. Sherlock didn't know whether he wanted to laugh or cry, though admittedly, he never really did much of the latter, the former was bubbling up in his throat until he was chuckling tearfully. It was John, _his_ John.

Sherlock reclaimed his position against the wall, this time holding something infinitely more precious in his arms. Chubby fists clung to his coat, just as dependent on Sherlock as he was of the infant. He needed it to be real; Sherlock was half afraid he would wake up and John would still be as dead as he was before.

John whimpered, and Sherlock lowered his nose to the soft crown of hair, feeling the silken strands tickle his cheeks, wet from Sherlock's tears.

 _Keep your eyes on me..._

 _Three years, Sherlock!_

How could he possibly have put John through that? Watching him jump off of Barts, that stifling, suffocating horror wrapped around every breath. Seeing John die, Sherlock had every intention of joining John, but he hadn't deduced _this_.

John whimpered and squirmed in his arm, one tiny fist coming up to hit Sherlock on the cheek. Sherlock stifled a smile. It was just like John to become violent in times of emotional turmoil.

Molly, who'd been silently watching their reunion, spoke up hesitantly, loath to break up the moment. "He hasn't had anything to eat," she said, fidgeting nervously with her fingers. "I wasn't quite sure what to do with him."

Sherlock watched John suckle on his fist, saliva drooping past his lip and sliding down his little fingers to land on Sherlock's coat. He didn't know what was to be done with John. Obviously he would take John back to Baker Street, where he belonged, but then what?

How long would the symptoms last, and for how much longer did he have his John before... Was there an inevitable death at the end?

"I think I might have a solution for your intriguing... situation."

Mycroft.

Sherlock turned, pulling the infant possessively to his chest. He wasn't going to let Mycroft take John.

Anthea strutted in just behind him, a bag on her arm and a bottle filled with milk. Mycroft nodded to Molly as he waved Anthea forward towards where Sherlock stood with John cradled tightly in his arms. "I rather thought my baby brother might be clueless in such a situation," Mycroft proclaimed haughtily, lifting his beak-like nose into the air. "You can stop suffocating the child, Sherlock. I'm not going to take him, which is also why I've come to speak with you, brother dear."

Sherlock relaxed minutely, though still held a squirming young John close to his chest and watched his brother through narrowed eyes. "What do you intend to do?"

Anthea came over, handing the bottle to Sherlock, still warm, and lowered the bag from her arm and onto the blacktop table. Sherlock held the bottle out, unsure what to do until Anthea looked up, rolled her eyes and held her hands out for John.

Sherlock growled, looking down at John, whose face had grown increasingly more pinched by the minute. Carefully, he handed the infant to Anthea, who cradled him gently against her bosom, and placed the nipple of the bottle against his lips.

At first, John whimpered, unfamiliar with the nipple and turned away from it as Anthea cooed nonsense at him, and he opened up.

Sherlock was transfixed at the tiny sighs as John began to drink, the way his fists flailed before coming to rest lightly on the sides of the bottle. Sherlock stood close, never wanting to venture too far, though quite aware he was intruding into Anthea's personal space. She had his partner, so he wasn't going anywhere until he had John back in his grasp.

Anthea carefully passed him back, folding Sherlock's arms into the right position to hold the infant as he fed, supporting the bottle as John suckled on the nipple.

"I don't _intend_ to do anything. Only to notify you that we are looking into the late Dr Förstner's past experiments and looking for a possible remedy for John. I... am not sure how long this could take, but until then, you will be responsible for his care. Of course, if you're not up to the task, I could arrange a nanny."

"No," Sherlock growled, frustrated at the thought of anyone touching his John, taking care of him. Mycroft smirked victoriously, the smarmy bastard. Of course Mycroft knew he would object, insufferable prat.

Mycroft tapped the tip of his cane against the lino. "Rest assured, however, you will not be leaving this room until you've been thoroughly primed on the care of an infant."

Sherlock stared down at John as he took a last pull from the bottle and turned away, breathing soft little pants that made Sherlock's throat close up.

Even if it was temporary and these small moments were what he had left with John, even if he was wading in deep waters, unsure and unfamiliar, Sherlock would savour the second chance he had with John Watson.

* * *

...

 **Day 3**

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, _**12**_

For the first time in years, Sherlock was exhausted. Even during his years away, navigating treacherous streets for days and going more than seventy-two hours without sleep, he'd been wide awake. Twenty-four hours with an infant-John and Sherlock was falling asleep on his feet.

John was an active child, happy and always looking for a distraction. Sherlock knew the feeling and wondered if John had often been as exhausted from attempting to entertain Sherlock.

He'd returned to the flat yesterday well into the day, and was on the verge of receiving a tongue lashing from Mrs Hudson on manners until she'd noticed John in his arms.

"Oh Sherlock, what- such a lovely child, but... whose is it?"

Mrs Hudson came close, grabbing a tiny fist between her fingers as John gave her a wide, toothless smile.

Sherlock didn't know how he would explain it to her, but to his surprise, she took it in stride, though she was still in awe. "I've never heard of such a thing in my life, but well- Sherlock, you've gotten a second chance with your John, even if it isn't quite what you expected."

Mrs Hudson teared up and held John close, still calling him doctor. "Doctor, I can't imagine what havoc you'll wreak on our Sherlock, but I'm happy to have you back." John bounced on his feet on her lap and let out a delighted squeal as she made faces at him.

Lestrade visited later that day, though his reaction was a bit more... dramatic.

As always, Lestrade pounded up the stairs making more noise than was necessary, startling John from a light nap in Sherlock's bed. He couldn't stop himself from pacing back and forth, going to check every five minutes for fear that John would disappear, suffocate, dissolve. As assured as Sherlock should be that it was not a dream now, every time John was out of sight, he felt dread claw up his chest, aching and gnawing. He'd end up at his bedroom door watching John's back lift and fall, his contented sighs as he slept peacefully.

Maybe one day, if John returned to his former self, _Sherlock's John_ , then he might consider a child in their future, but at the moment, John was enough.

John let out a startled cry as Lestrade called out for Sherlock, before beginning to wail.

Sherlock snarled and picked John up, shuffling the squirming infant awkwardly in his arms until he was holding him the way Anthea demonstrated at Barts.

" _What_ , you incompetent oaf, what could I have possibly done _now_ that you burst into my flat with your overgrown feet causing all that racket, and wake John!"

Lestrade froze, blinking at Sherlock and then at the baby, his features changing quickly to convey suspicion. " What the hell, Sherlock? What have you done?"

Sherlock glared, stepping back as he noticed Lestrade eyeing the child in his arms as if he weren't safe with him. "I've don't nothing, Lestrade. Now if you don't mind-".

Lestrade stepped forward cautiously, and Sherlock grit his teeth, ready to bite out something scathing to make Lestrade _back off_. "I realize you're mourning, Sherlock, but whoever that child belongs to, you have to give him back."

" _Whom_ ever, you fool, and he's mine," Sherlock spat acerbically. "Now get out. You've already ruined all of my hard work. It took me hours to get him to sleep!"

Lestrade stared between Sherlock and infant John, bemused as Sherlock bounced the child lightly in his arms, patting his back in what he hoped was a soothing gesture for him. He'd seen Anthea do it once after feeding John and then again, while putting him down for a nap.

If John insisted on staying an infant indefinitely, Sherlock was going to have to put him on some kind of sleeping schedule. Dull as that sounded, it was the only feasible course of action that Sherlock could think of. The lack of sleep would affect his concentration when he began the Work again.

"Tell me you're taking the piss, Sherlock," Lestrade said, running a hand through his salt and pepper hair tiredly. "You've got to be- there's no possible _way_ you've acquired a child between now and last night by any _legal_ means."

When Sherlock didn't so much as crack a smile, just stared back steadily, Lestrade's back straightened in alarm. "Sherlock, I'm going to have to report this," he began, reaching into his pocket for his phone.

"Don't," Sherlock shouted, the word echoing and bouncing off the walls, more open and vulnerable than Sherlock had ever allowed himself to be with anyone other than John. It felt wrong, but there were no limits to what he would do for John Watson. Not by far. "Even if I told you, you would have me sectioned."

"I'm thinking I made a mistake by not doing that already," Lestrade said, his expression speculative as his gaze flitted from Sherlock and back to the child in his arms.

Sherlock moved closer to Lestrade, afraid to let John go, but desperate to make the detective see. "What do you _observe_ , Inspector?" Sherlock left his question intentionally vague, wanting Lestrade to come to the conclusion on his own.

Lestrade shrugged, but peered closer anyway, bending down until he was eye level with the infant. "Cute little bugger, isn't he?"

Sherlock bristled, pulling the child back just slightly as he glared at the top of Lestrade's head. "Please refrain from calling John 'bugger' or any other inane words your silly little mind can manage to come up with."

Lestrade looked up at that, staring at Sherlock with a mix of pity and confusion. "You named him John?"

A loud, exasperated sigh of the long suffering kind. "No, his name _is_ John, Lestrade."

Lestrade stared and stared until the pieces of the puzzle finally began to fall into place, while Sherlock ignored him in favor of pacing with his nose shoved in John's hair, breathing in the smell of baby powder and Enfamil.

"You mean, when Förstner..." Lestrade gestured vaguely towards his neck, unsure how to proceed. "That's _John_... John _Watson_ , former army doctor, your partner who was pronounced dead last night?"

Sherlock froze, the child gurgling against his cheek, curling fists in his hair and pulling. John was such an aggressive infant, but Sherlock would rather have him that way than not at all. John was watching him again with his wise eyes, more knowing than any infant's had a right to be. Sherlock understood that John hadn't yet developed the cognitive ability to remember him or respond accordingly, but Sherlock whispered his affection for him anyway, the words lost to the excited, wordless squeals.

" _Hell_ Sherlock, what are you going to do?"

Sherlock turned sharply to the Inspector. "I'm keeping him. Mycroft is already involved and is looking into the situation. Until then, I'll be his caregiver."

Lestrade scoffed. " _You_ , Sherlock? The self-proclaimed sociopath who can barely take care of himself without John around to strong arm you into doing so! How could you possibly take care of a child, Sherlock?!"

"I can and I will," Sherlock sniffed loftily. "Come John, I think you've spoiled your nappy."

Sherlock turned, willing Lestrade to leave, but instead, the man followed him to the bedroom where the bag of nappies and baby powder were, along with the wipes. Anthea made it seem simple. For a woman who didn't have or want children, she was knowledgeable in the childcare area. Sherlock fumbled the first few times, but the fourth go was a success and now he considered himself a master of the skill. One must be a Jack of all trades.

Lestrade leaned against the door frame and watched while Sherlock settled infant John on his belly and rubbed his back in wide circular motions. Lestrade's perplexed gaze was a heavy weight on his back, but Sherlock was himself hypnotized with the way John's tiny chest lifted and fell. He was alive and breathing. John was _alive_.

The child fussed a little and Sherlock laid down beside him, placing a hand lightly on his back, feeling it move with John's breaths. He hadn't forgotten Lestrade's presence, merely blocked it out in lieu of giving John all of his attention.

"Do you remember when we met, John, six years ago in the lab at Barts," Sherlock began. "I was fascinated with you the moment I laid eyes on you. Of course I'll never tell you this when you're older again..."

Sherlock kept talking, even when John entered into his REM cycle, and well into the evening, long after Lestrade slipped out.

* * *

Because he'd allowed John to sleep so long, the infant stayed active throughout the night after having another bottle and well into the morning, when at last he fell asleep.

"Jooooohn," he whined as the infant tipped over on his chest, attempting to crawl up, though he still couldn't support his own weight. Blond hair curled at the tips, still slightly damp from the earlier bath, in total disarray from Sherlock's constant nuzzling. "You're evil," he griped, and John squealed, flapping his arms.

"Yoo hoo!" There was a knock at the door before it was pushed open, Mrs Hudson sidling through with a tray. "I brought you some food, dearie. Thought you might need it after a night with your little one. He seems like quite the active baby."

Sherlock watched her as she placed the tray in the table. Tea, sandwiches and a bowl of soup. Sherlock had never felt so grateful for Mrs Hudson.

"Would you like me to take him off your hands for a little while? No offense, Sherlock," Mrs Hudson said, wrinkling her nose and wringing her hands, "but you smell a bit raw."

Sherlock was reluctant to leave John, but he entrusted him to her care before eating a bit of the food and retreating to the bathroom to take a shower and brush his teeth. When he emerged, Mrs Hudson was downstairs with John, though he could hear her talking to him, explaining the Jeremy Kyle episode she was watching, and how scandalous it all was. Indeed.

Sherlock returned to the sofa and stretched out, already missing the weight of a small body beside him. How quickly he had already grown accustomed to this new facet of John Watson, grown attached. There was no part of John that would ever fail to fascinate him. Just the knowledge that he existed kept Sherlock pacified from that uninhibited fear and self-destruction.

Sherlock closed his eyes and slept with John's gleeful giggles smoothing the way to a peaceful slumber.

* * *

Sherlock roused to light shuffling against his chest, squirming and then stillness. He was warm, as was the tiny body lying on his chest, Mrs Hudson's quilt spread over them.

Sherlock listened to John breathing softly against his chest, placed his hand on John's back just to feel him breathe. The room was dark, sometime near midnight, he could tell, by the lack of traffic on Baker Street. There was the occasional break of light through the window as a vehicle passed and then the room was plunged into darkness again.

Sherlock closed his eyes, content for the first time since John breathed his last breath on dusty linoleum.

* * *

...

 **Day 4**

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, _**11**_

"What is that _thing_ , Lestrade, and why is it in my flat?"

The morning had been hectic, between bathing John, badgering Mycroft for progress updates on the analysis of Förstner's drug whilst changing and feeding John, and having to entertain Lestrade who had taken to channeling Mycroft and sticking his nose into everything, while trying to get John to sleep.

It was horrendous and a nightmare, and John was _evil_. Sherlock was used to lazy mornings and exciting evenings chasing down criminals and running through alleys. He was decidedly not prepared for parenthood and made up his mind that he would never be.

The infant pulled a little too hard on a patch of Sherlock's curls while he eyed Lestrade suspiciously along with the strange contraption he hauled up the flight of stairs. Ultimately, Lestrade would be hauling it right back down, because Sherlock was _not_ putting John in _that_.

Lestrade watched, amused, as Sherlock hissed and tilted his head to disentangle his hair from John's grasp, grimacing as the tiny fingers held on tighter. "It's a pram, Sherlock, surely you know what it's for."

Sherlock scowled. "I deleted it. It was unimportant. In what unlikely situation would John and I _possibly_ need to know what to do with a pram. But of course, John, always the unpredictable variable, goes and gets himself altered into an infant," he grumbled, wrinkling his nose as John pummeled it with his fist, giggling.

"Yes, well, you're going to need it. I just happened to have this one back from when Livvie was little, thought you might want to go out."

"I can carry him just as well," Sherlock replied, finally turning his attention to the pram.

"Alright, Sherlock, but... you should use it anyway, you know, get out of here for a bit. You've been cooped up since..."

Sherlock stared at the pram pensively. A little time out wouldn't hurt John, and they _were_ running low on milk for the tea. He looked back to John who was watching him curiously, and something about it was so similar to his partner, Sherlock's insides began to swell. He would recognize that knowing look anywhere.

He scoffed, though there was a smile threatening to break out over his lips. "Oh, don't give me that look, John, you know very well I have no idea what to do with this," Sherlock huffed, flipping his free hand towards the pram. "Not my area."

Lestrade shrugged, and pushed his hands in his pockets, his eyes fixed on John. "How is he?"

Sherlock pushed the hair away from John's forehead and pulled John's fist out of his mouth and reached for the dummy on the coffee table that was included in Mycroft's care package, and pushed it past John's lips. "As well as can be expected. He's taken care of, spoiled if I'm honest."

"Is he aware of anything... of you?" Lestrade was aiming for nonchalant, offhand, but Sherlock could hear the worry in his voice, the way it rose with concern near the end of his question.

Sherlock shook his head. "I can't be certain, but as far as I've observed - no. John probably isn't thinking about much of anything right now, but it's too early to conclude anything. Now that you've brought the pram, I may be able to get down to the lab and run some tests."

"Oh," Lestrade nodded, wiggling his fingers at John as the infant bounced excitedly in Sherlock's arms.

"While you're here, you might as well make yourself useful, Lestrade," Sherlock said, disentangling John's hands from his gown. "Watch him. I'm going to take a shower. I trust you not to do anything foolish."

Lestrade held John in his arms, staring at the infant in perplexity. Now that he was so close, his eyes widened as he noticed the similarities. "Christ, Watson, for as long as I'm breathing, I will never let you live this down." Then his eyes grew soft as John began to babble nonsensically. "Of course you'd survive this. Knew you couldn't leave old Sherlock alone."

Sherlock turned, his throat growing tight as he walked away, pretending he hadn't heard.

John wouldn't leave him, because Sherlock would follow him anywhere.

* * *

"Oh Sherlock, would you like some help with that, dear?"

What a stupid _stupid_ idea it was for Lestrade to lug this ugly, heavy death trap up the stairs instead of leaving it at the door like someone that used their mind would do. _Idiot!_ And why was it so _heavy_?! The idea was to carry a child who was less than ten pounds, yet it was built like a bloody machine. Ugh!

Sherlock had one large hand wrapped around John's back, curling up to support his neck while the other struggled with the pram.

"Of course I couldn't help with the pram, what with my hip and all, but I could hold John if you like."

"No, Mrs Hudson, that's quite alright." They were already halfway down the staircase, and it was a wonder that John hadn't already made an attempt at sabotaging his meticulously groomed curls.

Mrs Hudson huffed and crossed her arms. "Well it won't be alright if you stumble and break your neck being a stubborn young man. Here, give me that child, Sherlock." She walked up the steps and gently pulled John out of Sherlock's grasp, cooing softly at him. "Look at you, all wrapped up. Such a precious little thing."

John was dressed for the chilly weather in a cotton babygrow with mittens and a hood with animal ears, as well as a jacket to go over it all. When John returned to his former self with the intention of murdering the culprit for such dreadful clothing, Sherlock would be sure to point the finger at Mycroft. As loath as he was to admit it, Sherlock caught himself thinking the word 'adorable' more times than could be accounted for. It was out-of-character for him, and Sherlock wanted nothing more than to have his John back. He was becoming _sentimental_. Sherlock sneered at the thought and continued his struggle with the pram now that both of his hand were free.

"Off for the day, are we," Mrs Hudson enquired, rubbing noses with the giggling infant in her arms.

Sherlock, finally having successfully placed the pram on the ground floor, held out his hands to receive John and placed him into the pram, buckling him in the way Lestrade instructed before leaving. "Yes, John and I have a few things to take care of."

"Hm, that had better include you grabbing something to eat, young man. Despite your aversion to food, one can't go without for too long." Mrs Hudson left off with a maternal pat on his shoulder and a peck on the cheek, which she also did for John. "Now be good for Sherlock, John. Try not to throw a wobbly." Then she leaned down to whisper, "I don't think he'll know what to do if you did."

Correct.

"Apt conclusion, Mrs Hudson. There may be hope for humanity yet," Sherlock said dryly, before walking out the door, which Mrs Hudson opened for him and closed as he walked down Baker Street pushing, of all things, a pram.

Within five minutes of walking (too much involved to release John from the pram _and_ collapse it to fit in the boot of a cab when Tesco wasn't far, distance-wise), Sherlock realized that he missed his partner severely. There were memories on every corner, their reflection on every window, and of course, there was only the sound of his own footsteps and countless strangers. John had become a constant in Sherlock's everyday life, crucial to everything that made him, including how his mind worked. Before John, there was just the ever-present buzz of voices in the background, and the loud whirring of the inner-workings of his mind. With John, everything had come alive and into focus. Now, John was this tiny little life, but somehow, even in his current state, he brought purpose to the mundanity of life.

As Sherlock walked, people who recognized him cast curious glances from him to John, and the people that didn't merely ignored him and went about their daily affairs.

Tesco wasn't very far up the street and Sherlock's long strides ate up the short distance in less than ten minutes. He didn't want to have John out in cold weather for too much longer, conscious of the fact that even though it was his partner, his state of being was fragile for the indefinite future. Being that he was an infant (newborn upon discovery [day one], but seemingly accelerated growth in the past two days. Estimated at twenty-five to twenty-eight weeks; approximately seven months old), John was susceptible to colds, which could be harmful. Sherlock had made time to do his research, unwilling to take any undue risks with John's health.

Tesco was, as usual, was full of dimwitted housewives intent on stopping the flow of traffic to gossip and talk about their children whom they were eager to send off to boarding school, and young delinquents with sticky fingers. At least if you were going to steal, Sherlock would think one would want to learn the art of subtlety. Stealing and then bragging to your friends outside the main doors in clear view of CCTV was about as foolish as one could get. Once again, Sherlock despaired of humanity.

During their trip through Tesco, Sherlock kept up a running narrative on his disapproval of John's choice of shopping locale and how tedious it all was. "Of course I understand the convenience of the location, but really, John, how can you stand doing this so often? I would like to say I've never been amongst such a high level of stupidity in my life, but that wouldn't be completely honest. I suffer more than enough fools at the Yard as it is."

John merely issued a garbled comment and waved his limbs erratically as Sherlock continued his diatribe. He'd garnered more than a few stares, and by the time Sherlock was in the queue for checkout, people granted him more than a few feet of space.

No matter. Prolonged proximity to idiots was provocative at best.

After leaving Tesco, Sherlock finally conceded to the fact that he would have to take a cab to get to Barts. The tube was usually overcrowded and a cesspool that he was loath to expose John's new fragile condition to. The one good thing about the pram, Sherlock found, was that he could stow the milk in a compartment at the bottom and hope not to forget about it, lest he have to make another unnecessary trip back to Tesco.

Traffic was as congested as usual in central London but began to thin out near the hospital, and in under ten minutes, Sherlock was packing John into the pram and down into the basement where Molly would surely be.

John's garbled cries echoed widely throughout the empty hall, bouncing off the walls jubilantly.

"Yes, John, Molly should be waiting for us here. I know you're always nagging me to text her ahead of time, even if it doesn't do much good. I've already memorized her schedule years ago."

Sherlock hadn't realized how much he missed John's voice until it wasn't there to admonish him. John's propensity for scolding him wasn't sorely missed as much as the sound of his pleasant tenor, the moments of easy conversation between them, even his absent presence beside Sherlock felt like a hole in his side. He dearly missed his partner, but infant-John was proving to be just as much of a worthy distraction as adult-John. As before, he would take John in any form than not having John around at all. Sherlock had learned his lesson with the likes of Mary Morstan. Even now, Mary was a distant figure in the past, but he clearly remembered the nights without John, drinking his scotch alone on their wedding night, missing his best friend. It was hateful, a life without his partner.

 _I'd be lost without my blogger._

Those words never rang more true.

True to form, Molly was in the morgue when Sherlock backed the pram through the double doors, leaning over a corpse (Male, approximately 24-30 years of age; fisherman, fell overboard during storm and dashed his head on the hull) with a needle and thread. She flinched, startled, when John's loud greeting rang out throughout the room.

"Oh, Sherlock, John," she greeted, smiling softly at the infant. "I'm just finishing up, if you'll give me a moment, I'll show you where I have John's DNA samples. I'm sure you're going to want to have a look at them yourself."

"Not necessary, Molly," said Sherlock, turning the pram around to head towards the lab. "I know where you keep your results.

In the lab, Sherlock situated the pram to face the stool as he readied a sample of the blood that Molly initially extracted from John, and used a dropper to place a pearl of blood on a glass slide to place on the stage of the high-powered compound microscope.

With John preoccupied with his dummy and swinging his curious eyes around the room, Sherlock sat down to the microscope, adjusting the magnification and resolution until the round organisms came into view. Upon first glance, Sherlock could already see the difference in John's blood than a normal sample. The rate of mitosis was rapid in comparison to the normal division of cells. A process that should take hours was happening at a faster rate, jumping through the stages of mitosis is mere minutes. That was the reason for John's appearance, why he appeared to be aging quicker than was natural. Sherlock nearly regretted killing Dr Förstner, if only he could know the base components of his drug. Whatever the doctor had produced, it would have indeed been a huge breakthrough in the scientific community.

The chromosomes inside the cell's nucleus were replicating at an advanced rate, which meant that in a matter of days, John would possibly be nearer to age two. So how long would it be until he reached his forties? Weeks, maybe? Sherlock needed to know what was in Förstner's dose. He needed more data.

Sherlock pulled his eyes away from the lens and whipped his phone out of his pocket.

 **To: Mycroft**

 **Update.**

 **SH**

In the pram, John gave a little wiggle and cried out sharply, followed by a series of uncomfortable whimpers.

Sherlock checked the time. Time for John's lunch.

Sherlock reached for the baby bag in the compartment of the pram, just barely remembering the milk that was growing warm. He disregarded it and reached for the bottle of Enfamil he mixed before setting out. Sherlock released John from the pram and sat down on the stool with the infant in his lap, supporting John's body with arm and the crook of his elbow behind John's neck and upper back. Sherlock held the bottle to his lips and John parted his lips graciously, swallowing down the liquid with greedy sucks and loud breaths.

Sherlock decided he might consider (again) a surrogate mother, though he would prefer it to be John's child. Is this what their child would look like? John's clear, blue eyes and white-blond hair; chubby little fingers and toes, and John's signature knowing look. Even as an infant, he still looked at Sherlock like he was the centre of his universe.

"You're good at that, you know."

Sherlock didn't look up, kept his eyes on his partner, the only one he had eyes for. If John was himself, he would have teased him for being sentimental and then Sherlock would have kissed him because he could. It pained him that he couldn't.

He returned with a small "hm," and continued feeding John, the formula already down to half.

Molly walked further into the room, coming to stand timidly beside him, smiling gently down at the infant. "Do you miss him?"

 _You look sad when you think he can't see you..._

"Yes." Dearly.

John whimpered out a sigh and turned his head away from the bottle, leaving a translucent ribbon of milk and saliva to trail down his chin. He smacked his lips and turned to stare at Sherlock expectantly.

Sherlock's lips twitched, amused, as he lifted John to his chest and turned to grab a towel out of the bag to wipe John's lips clean with. Molly watched it all with a distant sort of curiosity, as Sherlock handled John with care, patting him gently on the back in what he hoped was a comforting motion.

Molly folded her arms across her chest and stared down her feet, licking her lips almost nervously. "Well, I'm here if you- if you ever wanted to talk or anything."

Sherlock's first reaction was to snap at her, to tear her down, anything to take attention away from his moment of vulnerability, but Sherlock found that he couldn't. Ever since the Fall, he'd developed a sort of camaraderie with Molly, and though he chose to distance himself, he still felt indebted to her. When he hadn't a friend in the world, or one that he could talk to at least, Molly was always there.

Sherlock turned to look at her, flashing a quick, but sincere smile. "Thank you, Molly."

Then, as if it never happened, the moment was over and Sherlock was placing John in his pram and stuffing the bag in the compartment at the bottom. "John and I must get going. In about half an hour, John is going to get fussy. Best nip it in the bud," Sherlock said, enunciating his words crisply.

Before Molly could reply, Sherlock was pulling the pram out of the room and down the hall, leaving behind his mess and a confused pathologist.

* * *

 **Text Message: Mycroft**

 **My people are looking into it. No news as of yet.**

 **Mycroft Holmes**

* * *

That night, John began to crawl, slowly, at first and gradually began to progress with the evening. Sherlock laid on his back over the bed watching as John crawled clumsily over his legs, smiling when the infant's chubby arms couldn't hold him up anymore.

John's babbling was becoming more formed around words Sherlock would say often, though they were still unintelligible. Sherlock watched it all closely with unhindered fascination, documenting it all only to add it to his mind palace in the wing dedicated to John. It was a rare and unobtrusive opportunity to observe growth rates and child development, but he was also a witness of John's childhood. With the new information, Sherlock wondered if his influence would somehow affect John as he grew back into adulthood.

Eventually, John tired himself out and fell asleep in the middle of the bed, his small snores the only sound besides Sherlock's own breathing. He considered playing his violin, but decided it would be better to stay where he could watch John. Sherlock tried to convince himself that it was purely for safety purposes and not because he was afraid that John would disappear the moment he left the room.

Sherlock had already stripped the blankets off beforehand - which he'd read was important to do when a baby was in the bed - so he sat back against the headboard and grabbed his laptop from the side table, prepared to spend a night keeping watch.

* * *

...

 **Day 10**

1, 2, 3, 4, 5, 6, 7, 8, 9, _**10**_

The next morning, Sherlock roused from his uncomfortable sitting position to find John standing next to him on the bed on wobbly legs, one hand on Sherlock's shoulder for balance. His hair was longer, blonde tendrils curling in disarray around the curve of John's ear and his teeth were beginning to grow in. John giggled and bounced on his legs as Sherlock lifted his head to stare wide-eyed. John was approximately eleven to twelve-months now, and Sherlock had fallen asleep and missed it!

The smell of a soiled nappy bombarded his senses, and John giggled again as Sherlock wrinkled his nose.

"Goodness John," Sherlock said as John plopped happily down back onto the bed, standing up to fetch the baby bag from the cupboard. "I might have to repeat the analysis on the contents of Enfamil. I'm not certain the smell emanating from your nappy is natu-"

A muffled thump cut him off mid-sentence and then a startled cry. Sherlock turned, his heart stopping as John began to wail on the floor. He hurried back, lifting John off the floor and into his arms, unable to stamp down on the rising terror as the child screamed in his arms.

"I'm sorry," Sherlock said tremulously, turning his face to nuzzle into John's hair, "I'm sorry, I'm _sorry_ , John. You weren't meant to follow me. I was coming right back."

Sherlock sat at the edge of the bed, rubbing John's back as he calmed down, as much to sooth himself as it was for the child. His fingers were trembling against the back of John's skull and back. The tiny body in his arms shivered and Sherlock felt a shame so strong he thought he might never be able to look John in the eyes again.

John's cries abated until he was whimpering quietly, his face pressing tears into Sherlock's neck, small fingers wrapped around Sherlock's tangle of curls. "Forgive me, John."

"Forgive me."

After the incident in the bedroom, the rest of the morning went smoothly. John didn't throw a wobbly in the bath and upon learning of John's jump in age, Mrs Hudson fed John bits of egg for breakfast. With John's accelerated growing rate, Sherlock was pressed to learn more about the care of toddlers, sure that he would wake up the next morning to a screaming two year old. _That_ was decidedly _not_ his area.

Fortunately, Mrs Hudson had plenty of experience from babysitting nieces and nephews, and was invaluable to Sherlock when it came to John's care.

At around noon, the telltale signs of light steps and creaking wood alerted Sherlock to a new presence ascending to the flat.

Mycroft, trying to lighten his load on the stairs. The ancient wood was practically screaming beneath his weight.

Sherlock was lying supine on the couch, his fingers steepled beneath his chin while John crawled around the flat floor, playing with a horrifically unrealistic baby blue rabbit Mrs Hudson had bought for him. John seemed to enjoy it, going by the giggles and claps coming from the floor, so Sherlock allowed it to continue to exist. He hadn't run a good experiment in days, so the bunny should count itself fortunate.

Sherlock showed absolutely no signs of surprise or welcome at Mycroft's uninvited entrance into 221B.

"Brother," Mycroft greeted lightly, stepping carefully over John as the toddler reached for his shined brogues with slobbery fingers. "Always nice to see your pleasant face. Fatherhood is treating you well, I hope?"

Sherlock sighed heavily, put out that Mycroft took the time out of his day to interfere. He purposely used any other means of contacting Sherlock's _besides_ texting, which he knew Sherlock preferred. "I hear your diet isn't going well for you, Mycroft. You nearly put a hole through the stairs on your way up. Rest assured, Mrs Hudson would have your head for that; not mine."

Sherlock turned, just in time to see Mycroft run a hand primly (self-consciously) down the front of his suit jacket. He smirked. Sherlock - one, Mycroft - zilch.

Sherlock sat up, putting their battle aside for the moment as Mycroft watched John curiously, the child chewing on the bunny ear with vigour. "What do you know?"

Mycroft didn't look away from John as he spoke, but Sherlock couldn't care less. As long as he was getting data.

"As it happens, we've not found much in the way of a cure, however, we believe the drug was created to target the DNA strand. As I'm sure you're aware after your visit to Ms Hooper's lab last afternoon, you've discovered the rate at which his cells are currently undergoing mitosis." Mycroft paused, staring as John abandoned the bunny and crawled to Sherlock, clumsily pulling himself up using Sherlock's knee as a crutch.

"Even in this form, Dr Watson is partial to you," Mycroft noted in a soft, pensive tone. He waited a moment before flicking his eyes up to Sherlock's. "You do realize there is always a chance he won't remember you."

 _Shut up, Mycroft._

Sherlock didn't answer, though his breath caught in his throat and he might have shifted a bit, uncomfortable with the thought of never being able to have those blue eyes turn to him in amazement. He wanted to hear John's lovely tenor, his proclamations of 'brilliant' and 'amazing', and most of all, he wanted John Watson back in the safety of his arms again.

"There's not much that we can do at the moment, but I am doing everything in my power to return your doctor to you with what little data I have to work with, Sherlock."

Sherlock nodded and sat back, pulling John into his lap. It was meant to be dismissive, but Mycroft lingered a little longer, just as captivated by John Watson as Sherlock.

* * *

...

 **Day 5**

1, 2, 3, 4, 5, 6, 7, 8, _**9**_

"Sherwah!"

"No, no John. Your pronunciation leaves much to be desired. Listen: Sher-lo-ck."

"Sherwah!"

"Oh, for goodness sake, John! You would think I was trying to teach you astrophysics. That would probably be easier." Sherlock flipped back against the couch, on which John was currently hopping excitedly under Sherlock's sharp eye.

Overnight, John had grown four inches and was walking nearly perfectly.

"Sherwah! Sherwah! Sherwah!" Unfortunately for Sherlock, John was also learning how to speak.

It was mesmerizing, watching John grow right before his eyes. No matter how long Sherlock kept his eyes on John, the changes were always subtle enough not to be noticed by the human eye. Once John was old enough, Sherlock would make a note to interrogate John on the changes his body underwent, how it felt, did he know when it was happening?

Sherlock caught John around the waist mid-jump and pulled him down, amused as the child giggled gleefully, struggling against his hold. "Business before pleasure, John," he chided playfully, the brush of soft strands brushing against the bottom of his jaw as John sat down in his lap, back-to-chest.

Sherlock held him close. "Now, where were we? Ah, Sher-lo-ck. Come now, John."

* * *

...

 **Day 6**

1, 2, 3, 4, 5, 6, 7, _**8**_

The day had started off well. Well, better than others. Now, Sherlock had a John that was approximately two years of age, and apparently, catching up on all the talking he'd missed out on. It reminded Sherlock of why he wasn't particularly partial to children, even if said child was his partner in an altered form.

"Sherlock, I'm hungry." Again. John had eaten half an hour ago.

Sherlock rose from his slump on the couch, gritting his teeth as he stomped to the door and pulled it open. "Mrs Hudson!"

A moment.

The door to 221A swung open, and Mrs Hudson poked her head out, eyeing Sherlock sternly. "What in heaven's name are you yelling about, young man?"

"John's hungry," Sherlock stated, rolling his eyes as Mrs Hudson's eyebrow raised smartly. "Yes, I know. Not my housekeeper, but surely you wouldn't allow John to starve."

John poked his head out the door beside Sherlock, flashing his baby teeth at Mrs Hudson in a wide smile. "Hi," he greeted jubilantly.

Mrs Hudson's demeanor changed as she regarded John, her eyes growing soft as the stern line of her lips eased into a smile. "Well, there's my handsome little man. Why don't you come down, and I'll set you to rights, dear. Heaven knows I don't want Sherlock to accidentally poison you with all that muck in the fridge."

John nearly sprang into action, but stopped and looked up at Sherlock in the last moment. It was such a familiar glance, the look John always gave him during a case, always so sure that Sherlock had a plan. It was so _John_.

Sherlock swallowed and nodded, afraid to speak as John grabbed the rail of the staircase with both hands and took each step down slowly. Sherlock stood on the landing until Mrs Hudson had ushered John safely inside her flat and closed the door.

Once inside, alone for the first time in days, Sherlock sat down in John's chair, wishing the man was there for him to hold, to hold Sherlock. John's scent lingered, the smell of spilt tea on the chair and the ruddy Union Jack pillow that John loved. Sherlock curled up facing the back of the chair and finally allowed himself to feel.

* * *

...

 **Day 7**

1, 2, 3, 4, 5, 6, _**7**_

Something was wrong. John's rate of growth had stopped overnight and he was exactly the same as the day before. According to the blood samples, John should have been, if not three, at least a few inches taller.

That wasn't all. John had developed flu-like symptoms: fever, chills, a cough, congestion, muscle aches and nausea.

Mrs Hudson had been gracious enough to help him out for most of the day, but Sherlock shooed her away when John finally fell into a fitful sleep.

As much as Sherlock would like to believe that it was related to John's growth, the fact that it hadn't happened before pointed to it being an entirely different situation. In fact, John had grown quiet around the evening the night before and went down easier than normal.

He'd slept with Sherlock on the couch, but John hadn't had an elevated temperature or any symptoms to speak of. He needed to know what was happening.

With a hardened resolve, Sherlock climbed the stairs to John's old room, which he'd been avoiding in the last week, to retrieve his medical kit.

Even though John never slept in his own room any longer, he still kept his medical kit there and a full wardrobe upstairs. Sherlock's wardrobe didn't allow room for any of John's things, what with the amount of space his disguises and bespoke suits took up.

It was dark and quiet and exactly the way John left it the night of the incident. The room smelled stale without John's scent to replace it, as if he'd been gone for months instead of days. The floor creaked as he walked across it, reminding him of the nights he would stay up waiting to hear it after one of John's unsuccessful dates. It always gave Sherlock a morbid sense of satisfaction that John would be as lonely as Sherlock was by the end of the night. He would rather not hear John happy with someone else if it wasn't him.

John's bed was still neatly made, tucked in curtly at the edges and the wrinkles smoothed out of the blanket. John hadn't slept in his own bed in ages. Sherlock's was significantly more convenient after a long case, somewhere close to fall into after stumbling through the door, exhausted after running through dirty alleys and hopping fences. Sherlock missed it.

He sat down on the edge of the bed and ran his hand over the blanket, mapping where John's would have done. He missed his lover. Sherlock missed falling into bed with him, breathless and sweat-soaked, the feel of John's legs wrapped around him. There were nights where John liked to be taken and others when John liked to take, and it never mattered to Sherlock, because either way, they would be close.

He missed the feel of a hard body against his own, John's calloused hands warming trails up his back, lips at his neck.

 _Sherlock…_

Sherlock wanted to hear his voice again.

He stayed there for a moment longer, reminiscing, before he remembered the John downstairs that he had a responsibility for. _This_ John counted on him. Without _this_ John, there would be no John at all.

Sherlock stood and walked to the cupboard and opened it, finding the kit on the top shelf. He needed to get a drop of blood from John in order to observe the rate of cell growth and whether or not it changed. John always had a sterilized needle in his kit.

Although it wasn't safe to run his tests at home without a certified medical personnel to supervise, Sherlock didn't trust getting others involved. If anyone else found out about John's condition, they would take him away and he'd be nothing more than a specimen. Sherlock knew, because he would have done the same if it were anyone other than John. No, no one could know, or Sherlock would never see John again. He'd be subjected to strangers poking and prodding at him for the remainder of his life, or what life he may have left. Only time could tell, but until then, Sherlock would do all he could to keep his partner alive, no matter the cost.

Loath to waste another moment, Sherlock snatched the kit and swept out of the room, taking the steps two at a time, the echoes of his own footsteps following him to the main room.

John was still sleeping when Sherlock returned to the room with a clean glass slide in hand and the medical kit in the other. He knelt down beside the bed, placing the kit down and lifting the wet towel on John's head to feel his forehead. Still a high temperature (estimation: 38.3 C). Two degrees higher than it'd been two hours before.

Sherlock pulled out a cotton ball and antibiotic cream. He laid them down, his eyes flitting up to John's face every so often, but the child merely slept on, his chest rising and falling faster than normal.

Sherlock used the hydrogen peroxide from the kit to sterilize the needle once more before gently handling John's ring finger (recommended to use non-dominant hand). John didn't move.

Sherlock made sure to pierce the dermis quickly, perpendicular to John's fingerprint, his gaze darting up to see John awake and staring at him distantly, lips drawn down into a teary frown. He still didn't move, but his whimpers were more pronounced. Quickly, Sherlock placed the slide under a drop of blood before setting it to the side. He dabbed the tiny pin prick with the cotton ball, holding it on the finger with one hand and pushing John's sweaty curls back with the other.

"I'm sorry," Sherlock whispered, feeling the small hand clench his tighter.

Sherlock stayed until John fell back to sleep, then took the blood sample back to the microscope at his desk.

Just like as before, Sherlock noticed the difference in John's blood cells right away. This time, however, the cells were not dividing as they would to create rapid growth. They were undergoing necrosis.

John was dying. Again.

Sherlock watched as the cells swelled until the membrane exploded, one after the other as if John's body were aging at a rapid pace, shutting down.

Sherlock pushed away from the table and grabbed his phone from where it sat beside the microscope. Mycroft answered on the first ring.

"Sherlock, how nice-"

"Mycroft, I need everything you have on Förstner's drug. There has to be some way to combat the drug in John's system, something I could come up with but I would need to see a sample-"

Mycroft, having stayed silent throughout Sherlock's monologue, finally broke in, every trace of condescension absent from his tone. "What happened?"

Sherlock paced, running the tremoring fingers of his free hand through his curls. "John's dying. I took another blood sample because he wasn't- he wasn't growing like he should, so I drew another blood sample. All of his cells are undergoing necrosis, self-destructing. He doesn't have long, Mycroft, send one of your lackeys - whatever you have to do."

Mycroft was silent, a moment too long for Sherlock as he pulled at his hair, thinking, thinking, he had to _think_!

" _Mycroft_! I don't have time for your games. Give me the samples and I will find a cure myself. There has- there has to be some- some kind of way that I can save John."

Mycroft sighed, though it was not the usual long-suffering exhalation Sherlock was used to. This one was saddened and a man burdened. "I'm sorry, Sherlock. There's nothing to be found. The test... whatever Dr Förstner injected John with, it doesn't appear in any of the tests we've run so far." A pause. The clink of glass setting down against polished wood. "I'm sorry, Sherlock."

"No, Mycroft you cannot do this! I forgave you the last time you turned on me, but if you do this, if you let John die… I will _never_ forgive you." So softly, Sherlock spoke the words, every bone in his body trembling with rage. He couldn't lose John. He would rather die first.

"Do not presume that I will allow you to blame me for this, _Sherlock_. This situation would not have happened had you not been so stubborn about everything," Mycroft growled, losing his composure for the first time in years, that Sherlock had heard. "You have always been and always will be your very own downfall. If John dies, it is on you. Perhaps next time, you will learn not to rush head first into the fray. Things don't always end the way you prefer them to. Goodbye, brother." Click.

The sound that issued from his lips was loud, raw and animalistic as he threw the phone, gaining minimal satisfaction as it clattered noisily to the ground. Down, down he went, spiralling, sinking to the ground as his world collapsed again.

He curled up with the cool wood pressing coolly through his shirt. His chest was hurting, imploding and his head swam.

Death was permanent, which meant John would never come back, which meant a world without John in any form.

In the other room, John coughed, the death rattle, it was called. It rang of permanency and inevitability. Sherlock didn't want John's last hours, minutes, seconds to be of a dusty ceiling and phlegmy hacks.

Sherlock pushed himself off the floor, walking numbly back to his bedroom.

He slid into the bed and pulled John into his lap, cradling him as he did nights ago, when the child was an infant. John was a warm weight in his arms, sweat soaking through his pyjamas as Sherlock held onto him, trembling. Sherlock left the lights off when it grew dark, but the curtains open to allow the moonlight to penetrate.

The hours passed and though his stretched out legs grew tired and his arms ached, Sherlock held steady.

John stopped breathing near midnight, his weak lungs heaving a last shuddering breath like an engine stuttering to a stop.

Sherlock held him for hours afterward, peppering kisses on his cold forehead, his tears falling like rain droplets upon John's grey cheeks.

Sherlock pulled his fingers through the crown of soft hair, rocking John's small body back and forth. He hid his face in John's hair and bit his lips to keep the sobs from tumbling out.

As John's limbs grew stiff, Sherlock thought of ways to go, too.

* * *

…

 **Day 8**

1, 2, 3, 4, 5, _**6**_

Sherlock opened his eyes to grey light pouring through the window and the sound of clinking crockery. Somewhere in the flat, music played from a radio. He didn't even _own_ a radio.

John was gone as well.

Who would _dare_ to come into his flat and take John away? Sherlock was going to take him to the morgue, but he wanted time first. Now, John had just been snatched away.

It smelled like Mycroft's handiwork.

Sherlock growled, jumping out of the bed. His clothes were damp from John's sweat the night before and his face felt stiff from dry tears.

He must've looked a fright, but he didn't care. Sherlock tore down the hallway, intent on tearing Mycroft, or whoever he'd sent to do his dirty work, to shreds.

However, that all went out the door when he turned the corner into the kitchen. This was most definitely not Mycroft.

Short stature, approximately eighteen to twenty-three years of age, blond hair, presumably dark blue eyes, no muscular development yet, however.

There was an old Beatles song playing on the telly, though it was loud enough to certainly replicate a radio. Sherlock looked from the telly and back to the young man in his kitchen, who just happened to look like a _certain_ picture of a _certain_ teenager.

Sherlock must have made some noise he wasn't aware of, because the young man turned.

It was John, but about twenty years younger.

"Oh, morning," John greeted, smiling nervously when he didn't receive answer. "I'm sorry, I just thought I'd do some cleaning while you were sleeping." John grabbed the remote off the kitchen table and switched off the telly.

Sherlock stared, shaking his head slowly, distantly as he stared at the younger male. How could… overnight?

Two to twenty was a large leap, but then again, John's heart had stopped, he'd died in Sherlock's arms and grown cold. Now he was…

John cleared his throat, widening his stance a bit as he stared back at Sherlock. "Perhaps you can tell me why I woke up in your lap," he muttered, running a hand over the nape of his neck.

And his voice, Sherlock thought to himself, he'd missed that voice.

When Sherlock failed to come up with a response, John nodded. "Right. I'll just… see myself out then."

Before John could go far, Sherlock's hand darted out to catch John's sleeve. He was wearing one of Sherlock's shirts. "Wait, please. I'll- I'll explain everything."

John blinked, looked down at Sherlock's hands and then back up to his face. It was unfamiliar, looking at this version of John, so young and his face clear and unlined. He was everything Sherlock would have gone for in uni, and as his middle-aged self, John also ended up being everything Sherlock went for well into adulthood.

"Alright," John conceded, slowly pulling his shirt out of Sherlock's hold and headed towards the couch.

Sherlock joined him a moment later, sitting in his customary chair, and folded his hands under his chin.

"So I'm assuming you _didn't_ pick me up at pub or any of that…?"

Sherlock shook his head no, and regarded John steadily. "You wouldn't believe me if I told you."

John smiled with a cocky little twist to his mouth, shrugging. "Try me, Sherlock." The words were out before John realized it, and surprised, he touched his fingers to his lips.

Sherlock's back straightened, his eyes narrowing. "I never told you my name."

"You didn't," John agreed. "I dunno. It just sort of seemed like the right thing to say." John stared at the ground with a faraway look, bemused, before his eyes shot up to Sherlock's hopefully. "Did I get it right?"

"Yes," Sherlock murmured, his mind running at high speed. "What else?"

John shrugged. "That's all I've got at the mo'."

John stared at him expectantly, his hands folded patiently in his lap as he waited for Sherlock to explain.

"Your name is Captain John Hamish Watson, late of the Fifth Northumberland Fusiliers. Along with achieving the rank of Captain whilst serving in Afghanistan, you were also an army doctor. We met after you were discharged from service due to a bullet wound to the shoulder that affected your fine motor skills – tremors - and a psychosomatic limp. We met six years ago through a mutual acquaintance, Mike Stamford…"

The story took well over an hour, but the more Sherlock spoke, the lighter the oppressive weight on his shoulders became. For his part, John didn't say much, only interrupting to ask a question here and there, but mostly he seemed enraptured by the story that Sherlock began to unravel. He wrinkled his nose whenever Sherlock mentioned the experiments, the body parts in the fridge, and his eyes grew darker as Sherlock delved into Moriarty's machinations and Sherlock's subsequent Fall. John's breath caught when Sherlock mentioned their change of relationship after John's divorce from Mary and grew sad during the story of his own death. Empathy. Even when John didn't understand fully, he still empathized with Sherlock over his own untimely demise. Amazing.

When it was all over, John seemed speechless, and Sherlock was watching for any reaction.

Finally, John slumped back into the couch. "Wow. I hope you don't mind me saying, but this all kind of hard to believe. Perhaps, you could maybe, show me a picture of Dr Wat- I mean _me_."

"Fair enough," Sherlock answered, standing and going to retrieve the old picture of John from the room and a few recent ones. Most of them were newspaper clippings from past, high profile cases.

He returned to the living room and joined John on the couch, though kept a respectable distance between them, and held out the photos.

Sherlock showed John the picture of his younger self, approximately at the same age (same white-blond hair, identical stature and weight, upturned nose, thin lips), and John took it with some hesitation.

John's eyes grew wide as he stared at the photo. "Those clothes… it must have been the eighties."

"Indeed," Sherlock agreed, handing John the photos of his older self.

"'The Boffin, Sherlock Holmes and his assistant, Dr John Watson,'" John read, tracing his fingers over the picture of Sherlock and John standing outside of 221. "So I'm a doctor," John smiled, staring down at the future.

"A damn good one, too," Sherlock commended, his lips twitching as he too stared at John's older self standing beside him. "Also my blogger."

"Your blogger," John asked, surprised.

Sherlock nodded, rolling his eyes. "Of course. You write up all of our cases and cloud them with sentiment and terrible titles that idiots find catchy."

John smiled. "Well you seem quite fond of it."

"It has its advantages," Sherlock returned nonchalantly, though his insides were growing warm with the progression of their banter. That was another item on the long list of things he missed about his partner.

"So… we were together?" Sherlock nodded, staring at the clipping of them still held in his hands. "So does that make me… am I…?"

Sherlock looked up sharply, regarding this younger John with stark intensity. It almost had the same uncomfortable atmosphere as their first dinner together at Angelo's. "Are you what?"

John rubbed the back of his neck, his eyes looking everywhere but at Sherlock. "Am I gay?"

Sherlock smiled grimly. "Not necessarily. As I relayed earlier, you _did_ have a wife, and before that, a constant line of women traipsing in and out of our flat. It really was inconvenient, especially to the Work."

John hummed and nodded. "So you're the only guy I've ever been with?"

"No."

"Oh… who else?"

Sherlock shifted, growing uncomfortable with the direction the conversation was taking. It felt as if he were telling secrets that were not his to tell, but then again, he _was_ telling John his own biography. "Your ex-army commander, Major James Sholto. It was a brief fling during your time in Afghanistan, but even after, the two of you were quite close until he was injured in an ambush and he was invalided back to Britain. You invited him to your wedding, in which he was nearly murdered by your wedding photographer."

" _Oh_ ," John said more to himself than to Sherlock. "What a way to live a life."

Sherlock nodded once, graciously. It was true. His life had always been peculiar, and most of it was by his own doing, but after John, life was a kaleidoscope of color, brilliant and magnificent, and ever-changing.

"Hm…" John tapped his fingers on the knee of his trousers (an old pair of John's), and smiled cordially. "Tea?"

Sherlock froze, his eyes widening slightly as he looked at the younger John. If there were any doubts about the young man's identity before (which there weren't), there certainly weren't anymore. Even at a young age, John relied wholly on the benefits of tea to cure any situation. Sherlock smiled, his cracked lips stinging with the action. He wanted to laugh, to laugh and laugh and pull John towards him and _kiss_ him, but it wasn't quite _his_ John yet. Not quite.

Sherlock stood. "I'm going to take a shower."

"Sure, yeah," John said, waving him off and retreated to the kitchen.

Sherlock took his time in the shower, washing the dried sweat off his body, John's sweat off his hands. He thought about the drastic change overnight, the leap in age. It was as if John's body had undergone metamorphosis, not unlike a butterfly. John died. Sherlock held him through it, felt his body stiffen with rigor mortis.

Did he die, only to come back years ahead, a stronger body that could sustain him as it changed rapidly? The bigger question was, would John stop aging once he reached the point in which he'd been before? Or would he speed past the rest of his life to a certain death from the symptoms that came with old age?

Sherlock couldn't watch John die again… That would be…

Sherlock leaned his hands against the shower wall, allowing the water to soak his hair. Drops of water ran streams across his face before falling down into the drain.

Two times was more than enough.

When Sherlock emerged from the bathroom, he crossed to his bedroom, unmistakably hearing two voices in the sitting room. A man, by the low hum of his voice.

He changed quickly, once again able to wear his suits without the fear of a terribly young John wreaking havoc on the silk of his shirts or the expensive fabric of his trousers. He left the jacket off for the time being and walked into the sitting room.

"Oi, Sherlock! You weren't answering your phone, so I thought you might have had your hands full with John. Seems I didn't have to worry too much."

"Lestrade," Sherlock nodded. Lestrade was seated on the couch with John, two cups in front of them on the coffee table and the other growing cold on the desk. Lestrade's body was turned towards John, displaying interest in the conversation as well as signs of attraction, as he often did with John even before the incident. A blush was just beginning to fade from Lestrade's cheeks.

Sherlock narrowed his eyes and settled in his own chair a ways from the couch, though he had a clear view of John and Lestrade. John merely conveyed curiosity and intrigue. Of course he was intrigued. He'd just found out that he was a middle aged man in a body twenty years younger than he should be.

Sherlock stomped down the jealousy, feeling rather foolish. Lestrade would never cross the line with John, and was more than aware of his connection to Sherlock. They never hid their relationship when they were together, though neither of them had been openly affectionate.

"Mycroft told me what happened, said I would be better received," Lestrade said, talking around the rim of his cup before taking a sip.

Sherlock crossed his legs and sat back in his seat, his fingers itching for the violin after days without. He longed to block out the noise of Lestrade's voice and think about something other than John for the first time in a week.

"Yes. Mycroft and I are no longer speaking."

That was all he was going to say on the matter. Before Lestrade could carry on with that conversation, Sherlock turned to John, effectively cutting Lestrade out with his body language. "John, I'll need to take a blood sample."

John shrugged, taking another sip of his tea with a content smile.

Sherlock rose to retrieve the medical kit from the bedroom and returned to see Lestrade shrugging on his coat.

"Well, looks like everything is fine here. I'll let your brother know so he'll let me get on with my real job," Lestrade said as he headed to the door. "It's good to see you doing well, John. Sherlock, I'll let you know if I get anything up your alley."

Sherlock nodded and headed to the couch, reclaiming his seat next to John who calmly set his cup down and began to roll up his sleeve. "Are you like that with everyone?"

The question caught Sherlock off guard, unexpected and abrupt as it was. He froze, lifting his head to look at John. "Like what?"

John fidgeted. "Some would say brusque, I would say a prat."

Sherlock lowered his head, covering the tiny smile pulling at his lips, as he dug into the kit for the supplies he would need. "Yes, well, if you're asking whether I'm a sociable person - no. People aren't my area and if I spent all my time mincing words, I would never get anything done."

John tilted his head, staring back with empathetic blue eyes. His John, always the understanding one. "I'm assuming you don't attract many friends with that sort of logic."

"You'd be assuming correctly. I don't have friends."

 _I've just got one._

"Sure you do," John stated, so calmly and with so much conviction that Sherlock's breath caught in his throat. "I'm your friend."

Sherlock didn't look at him, was afraid that his face would betray the swell of emotions swimming behind his gaze. His mouth, however, had always been uncontrollable. "More than."

He did look up then, pale eyes staring back into John's with restrained fervor. He reached for John's hand as the younger male held his stare with that familiar hint of defiance. John looked away first and Sherlock followed suit afterwards, turning his attention back to the blood sample.

Sherlock used much the same method as the night before; just a finger prick to extract a drop of blood onto a glass slide. He left John with a cotton ball and antibiotic cream, trusting that he knew rudimentary first aid. It seemed that John had retained knowledge and was still moderately intelligent, yet he didn't remember names, faces, or even events of his life. Sherlock could at least conclude that the limbic system in the medial temporal lobe may have been affected by Förstner's drug, some sort of damage to the hippocampus which would in turn have resulted in retrograde amnesia.

John didn't have any pre-existing memories, and whether or not he suffered from anterograde amnesia as well was as of yet undetermined. Sherlock would have to wait some time to see if John was capable of retaining the information.

Sherlock sat at his desk and slid the glass on the microscope stage, adjusting the lens and resolution until he could see the tiny organisms swimming around. They appeared healthy and red, and multiplying much faster than they had the day before. There were twice the number of cells undergoing mitosis, as if making up for the ones that self-destructed. It was miraculous and unlike anything Sherlock had ever seen before. "Did you feel it," he asked, keeping his eyes pressed against the lens.

John who'd been reading the paper on the couch, turned to Sherlock, confused. "Feel what?"

Sherlock hesitantly tore his eyes away from the lens and regarded John impatiently. "Did you feel it when you changed?"

John's eyes shifted to a point behind Sherlock's shoulders, his eyes growing distant. "I woke up this way, but since then, it feels like my skin is constantly tingling. My shoulder, especially, is nearly unbearable." As he spoke, John reached back to itch the skin of his shoulder, exactly where the gunshot wound should have been. The shirt was large enough of John's smaller frame that he could push it back a bit. Sherlock could see a patch of skin where the exit point of the wound would be, growing puffy and irritated.

"I know it's the bullet wound."

Sherlock's eyes widened at John's surprising astuteness. "How?"

John ran a hand through his hair, suggesting nervousness as he stood to pace. "I- I don't know. Throughout the day I've been seeing random flashes of pictures, names I've never heard before. I know I have a sister; I know what she looks like but I can't remember her name. I only get these feelings of the connections I have with people, which is why it wasn't much of a surprise that you and I were… you know, together."

John sighed, stopping by the desk. "Can you see them, my cells?"

Sherlock nodded and stood, offering John the seat. "Take a look."

John sat at the desk and pressed his eyes to the lens, exhaling quickly as he observed the process of cell division, the organisms splitting. "Brilliant," John breathed, though he missed Sherlock's reaction as he raised a hand to his mouth quickly, and then turned away before John could see. "This isn't normal, is it?"

Sherlock breathed, waiting for his heart to slow down, before he removed his hand and responded. "Not at all. The division of cells is a primary factor in aging, which means that even at this very moment, you are getting older. At this rate of mitosis, it won't be days before you reach middle-age."

The very thought exhilarated Sherlock. To know that in possibly a day, maybe hours, his John would be there with him, where he should be.

By midnight, John was noticeably older. A few of John's familiar signs of age were beginning to emerge, the smile lines at the corner of his lips, and the wrinkles on the sides of his nose.

John fell asleep on the couch, still unsure of his place in the flat, and Sherlock couldn't bring himself to leave him there. He kept up a vigil throughout the night, hoping to see his lover's face with the coming of dawn.

* * *

…

 **Day 9**

1, 2, 3, 4, _**5**_

When John reached approximately twenty-eight to thirty years of age, the cell replication began to slow, and John recalled snippets of his time in Afghanistan.

Sherlock sat with him through the nightmares.

* * *

…

 **Day 10**

1, 2, 3, _**4**_

At approximately thirty-two to thirty-five years of age, John's bullet wound emerged and the fall out was devastating.

John remained in bed throughout that day, his body shivering as the wound visibly grew infected and John called out names Sherlock didn't recognize. Mrs Hudson did what she could, providing fresh linen when John soaked the sheets with sweat and chicken soup when John was coherent enough to eat.

At night, John's moans quietened, and the infection receded as his body changed again.

Sherlock had been determined to watch for the metamorphosis, but by that time, he hadn't slept in days. He fell asleep in a chair next to the bed with John's warm hand in his.

* * *

…

 **Day 11**

1, 2, _**3**_

The next day, John walked with a limp and held himself like a wounded man, unsure of his place in the world, in _their_ flat. This was the stranger Sherlock met in the lab, the one that was on the verge of suicide and the very same one who'd gained redemption through two glass panes in an entirely different building.

That night, in his sleep, John spoke.

 _"Sherlock."_

Sherlock drowned.

* * *

…

 **Day 12**

1, _**2**_

In the morning, John remembered bits and pieces of their life together. In the afternoon, he asked about Mary over Thai, and about the two of them over tea in the sitting room. He was so close to John, he _was_ John, and Sherlock was euphoric with the inevitability of John's return.

Sherlock could feel it, the way John's eyes began to linger on his form, the electricity when their arms brushed. Sherlock began to do it purposely to see John's reactions, to indulge himself his own guilty pleasure in being able to touch his lover again. He wanted to hear John's breath hitch, the way his pupils dilated at Sherlock's proximity.

Sherlock watched him and John watched in turn, smiling wryly over a book.

"We were lovers," John said that night. Not a question. He remembered.

They'd been dancing around each other all night.

Sherlock smiled. "Yes."

"Do you still feel the same, after having to change my nappies, that is," John teased, but the way his fingers tapped nervously on the arms of his chair told of his anxiety.

Sherlock shrugged. "I nearly changed my mind on one instance. It was the Enfamil." Sherlock smiled. John giggled and everything felt right again. Then he grew serious, his eyes growing sober as Sherlock held John's stare intensely. "If anything, your time away has only made me want you more."

* * *

John's skin was slick beneath his hands, though this time, not with the sweat of fever dreams or blood from a gunshot wound made by an invisible bullet. John trembled beneath Sherlock's touch, though not from nightmares. John's cries echoed in his ears, but out of pleasure, instead of pain.

It was only a matter of time before they found themselves this way, together again and Sherlock was done dancing, done waiting. It felt like a lifetime, it _had_ been a lifetime since he'd had John in his arms in this way; John's thighs bracketing his hips and the sweat of minutes, hours of their bodies sharing heat, pasted together by sheer will and intent.

" _Sherlock_!" And Sherlock made him say it again and again and again, because it'd been too long since the last time he heard John speak his name.

' _Sentiment_ ', he used to sneer, hated the very idea of it, but now sentiment had Sherlock cramming his face in John's neck and willing himself not to collapse on top of John. He wanted to rage, to plunder, to take, to keep John forever and lock him away. No one would ever take John again.

Sherlock was obsessed with the very idea of keeping John safe, keeping John by his side. John was his lifeline.

* * *

…

 **Day 13**

 _ **1**_

Sherlock kept John in bed for most of the day, telling John case stories that he hadn't remembered yet, in between bouts of sex.

Near the evening, Sherlock took another blood sample from John.

The blood cells were behaving normally.

Sherlock felt triumphant and John was _his_ John again.

In the bedroom, they stretched languidly over the duvet as John recalled more than he had earlier in the day. He was beginning to remember the last case.

Sherlock fell asleep knowing that it wouldn't be long.

* * *

…

 **Day 14**

It was three in the morning when John remembered everything. He didn't yell or scream or cry, but turned and placed an arm over Sherlock's waist, pressing his chest to Sherlock's naked back.

Sherlock had been finally drifting to sleep, but the urge to turn over was strong, and so he did.

John's eyes gleamed in the dark like magnificent gems. They were glossy with unshed tears.

"Sherlock," John gasped, his chest heaving. "Sherlock, you-"

John broke off, leaving his sentence fragmented and open, but Sherlock understood.

John sobbed into his chest and Sherlock pulled him closer, his own tears falling into the crown of John's hair. Sherlock knew that John had questions, too many to answer just yet and a thousand more that he didn't know the answer to.

Without Dr Förstner's analysis of the drug, Sherlock would probably never be able to answer John's questions, but where it would have mattered two weeks ago, that in a way Förstner won, it didn't matter. Relief flowed through him like a stream, washing away the tragedies of the weeks past. He would always remember the time he nearly lost John, but now that Sherlock had him, he wouldn't let go for anything.

"John…"

John looked up at him with reddened eyes and said, "So I guess it's safe to say you've known me for a lifetime, now?" Then he giggled.

Sherlock laughed - _laughed_ \- and it never felt better.

His John was back, after everything. Fourteen days of discoveries, fourteen days of coming to know every facet of John Watson. Fourteen days of coming to love John again and again in every way, in every form. Fourteen days in which John died and was born anew.

Sherlock kissed John.

Fourteen days, or rather the transformation of John Watson.

* * *

_/\\_/\\_/\\_/\\_/\\_

 _"I hope you feel things you never felt before. I hope you meet people with a different point of view. I hope you live a life you're proud of. If you find that you're not, I hope you have the strength to start all over again."_

Eric Roth, _The Curious Case of Benjamin Button_

Fin.


End file.
